2020 GMC Sierra 1500: More Diesel, More Speeds

GMC’s new-for-2019 Sierra 1500 took a less controversial styling route than its Chevy Silverado sibling while retaining the numerous upgrades foisted upon the next-generation pickup twins. For 2020, GMC tweaked the light-duty Sierra’s offerings just a bit, hoping to lure more finicky buyers into the model.

For starters, GM’s 10-speed automatic transmission has a new engine to mate with, hopefully boosting fuel economy ratings that fell for the 2019 model year.

The move to a brasher front end for the next-generation design led to an MPG downgrade for models equipped with the 5.3-liter V8 engine, despite the fact that the new trucks shed weight compared to their predecessors. GMC now says the 10-speed will be available with the 5.3L equipped with Dynamic Fuel Management, GM’s fancy new cylinder deactivation system. The previous transmission pairing was an eight-speed auto.

For 2020, GMC makes the 5.3L/10-speed combo “standard on the Sierra Denali and Sierra AT4 and available on all four-wheel drive Sierras with the SLE trim level and above.” It’s worth noting that the SLE and Elevation trims carry a standard 2.7-liter turbo four-cylinder, mated to the eight-speed auto.

That engine earned praise for its power, but not for its fuel economy.

While the addition of the smooth 10-speed to the smaller V8 engine is a welcome upgrade, higher-end buyers will probably remain tempted by the optional 6.2-liter, a favorite among TTAC staff.

If less displacement and greater torque is what turns your metaphorical crank, the 3.0-liter Duramax inline-six turbo-diesel, which appeared in the Sierra lineup as a late-2019 addition, continues onward. The 277 horsepower, 460 lb-ft mill can be ordered in Denali, AT4, SLT, Elevation and SLE trims. For 2020, however, buyers can pair it with GMC’s pricey, prestigious, and seemingly indestructible CarbonPro bed — another late addition to the lineup. Only the top-flight Denali and runner-up AT4 see this build configuration.

Also new for 2020? The brand’s Adaptive Cruise Control – Camera system becomes available on SLT, AT4 and Denali trim levels, allowing the truck to come to a full stop with the cruise control set. The ProGrade Trailering System, a trick camera setup that turns your trailer invisible for easy rearward viewing, also appears on the 2020 Sierra options list. The system debuted on the redesigned 2020 Sierra HD.

[Images: General Motors]